Basically I mean that will a negatively charged body make a better magnet, since unpaired electrons are the source of magnetism in ferromagnetic materials.
So after negatively charging a material We now have many unpaired electrons enabling the creation of a good magnet.
Is this perception of mine correct?
This is too simplistic. You have to remember that there are three basic types of magnetism: paramagnetism, systems with unpaired electrons but no magnetic ordering - transition metal complexes are examples; anti-ferromagnetism (AFM), systems where the electrons become magnetically coupled into 'up-down' pairs greatly reducing magnetism and ferromagnetism (FM) where again electrons become magnetically coupled but this time they are aligned 'up-up'. Which situation is present also depends strongly on the structure of the material. It follows that just because you have unpaired electrons it doesn't follow you'll have ferromagnetism. The only way to know is to measure the magnetism over a large temperature range and see if the magnetism decreases to almost 0 at 0 K (AFM), increases smoothly (paramagnetism) and increases and then increases more sharply (FM). Wikipedia has a nice description of all of these types of magnetism.
Max, who told you that in non-FM materials all electrons are paired? This is not true. They simply are not aligned (more precisely, their spins are disordered giving rise to a zero mean FM magnetization). The pairing of electrons (called Cooper pairs) occurs only in superconductors. Therefore, magnetic properties of superconductors are totally different from any ordered magnetism (like FM, AFM, etc). The only reason for existence of FM (AFM) structure is alignment (anti-alignment) of electron spins which has nothing to do with any "pairing". Therefore, your perception is incorrect.
It is the net spin of electrons which is responsible for Ferromagnetism. Electron injection may directly influence the Curie temperature. For example, for most of the double perovskite materials, it has been reported by many researchers that electron addition may strengthen the exchange interaction, resulting in the increased transition temperauture.
Imad, you are talking about improving the existing FM properties (thru increasing Curie temperature) by injecting polarized electron spins. Which is of course true.
Max is talking about turning an inicially non-FM material into a ferromagnetic one simply by adding extra electrons. This is impossible.
Professor Sergei Sergeenkov, i totally agree with you and i have fully understood the question. You and Dr. David J Harding have already explained the query.After seeing your answers, I assumed for a while that Max Emmanuel would have got the answer. My answer was an extension explaining the effect of electron addition. Thank you
Max, serious people are still awaiting your reaction. Don't let them down. OK?
Thank you all for your answers.
We all agree that magnetism comes from charges and by increasing the charge of a body we are taking it closer to being a magnet.
Now when we have injected more electrons into a body and give these electrons kinetic energy we shall be creating a better magnet. You are basically having charges in a body moving randomly and generating a magnetic field.
This is why I believe that heating up a ferromagnetic body to a considerable temperature will make it's attractive force to a magnet bigger.
Max, we all DISAGREE that magnetism comes from CHARGES because it comes from electron SPINS.
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